Polyphenylene sulfide (hereinafter also referred to as “PPS”) resins have good characteristics as engineering plastics including high heat resistance, good barrier properties, high chemical resistance, good electrical insulating properties, and high moist heat resistance, and therefore they have been widely used, mainly in the form of injection moldings and extrusions, as material for different electrical/electronic parts, mechanical parts and automobile components. PPS resins, however, are generally lower in toughness than other engineering plastics such as nylon and PBT, which restricts its uses, and their improvement is now strongly called for.
Studies have been carried out on compositions consisting of a PPS resin and a polyetherimide (hereinafter also referred to as “PEI”) resin or a polyether sulfone (hereinafter also referred to as “PES”) resin. For instance, JP-HEI-4-130158 (claims) has disclosed a resin composition consisting of a polyarylene sulfide resin, PEI resin, and organic silane compound. This document, however, contains no description that suggests the possibility to achieve a high toughness by using a fine dispersion of a PEI resin. Moreover, it does not address the volume of alcohols that can generate from an organic silane compound when such a resin composition as above is thermally melted. JP-HEI-5-86293 (claims) has disclosed a resin composition consisting of a PPS resin, PEI resin, and a silane coupling agent containing one amino or epoxy group, but gives no description on the possibility of achieving a high toughness by finely dispersing the PEI resin. Moreover, it does not address the volume of alcohols that can generate from a silane coupling agent when such a resin composition as above is thermally melted. JP 2001-261959 (claims) has disclosed a biaxially orientated film with high dielectric strength and good electric characteristics that is produced from a resin composition of PPS and PEI. JP 2001-261959, however, has no description on the addition of a compound that contains at least one of the epoxy group, amino group, and isocyanate group. It gives no description on the possibility of achieving a high toughness by fine dispersion of the PEI resin. Moreover, it does not address the volume of alcohols that can generate from thermal melting. JP 2003-268236 (claims) has disclosed a resin composition consisting of a polyarylene sulfide resin, PEI or PES resin, and graphite, and in a detailed description of the invention, addresses the addition of an alkoxysilane compound containing an isocyanate group. However, any embodiment given in the document contains a description on an alkoxysilane compound containing such an isocyanate group as above, and its effect has not been known. Further, no description is given on the possibility of achieving a high toughness by fine dispersion of the PEI resin. No description is given, moreover, on the volume of alcohols that can generate from an alkoxysilane compound when such a resin composition as above is thermally melted. JP 2003-147200 (claims) has disclosed a resin composition consisting of a polyarylene sulfide resin, PEI resin, carbon black, non-carbon-black non-fiber filler, and fiber filler, and the detailed description of the invention mentions the addition of an alkoxysilane compound that contains an isocyanate group. The embodiments in JP 2003-147200 contain no description on an alkoxysilane compound that contains such an isocyanate group as above, and its effect has not been known. Further, no description is given on the possibility of achieving a high toughness by fine dispersion of the PEI resin. No description is given, moreover, on the volume of alcohols that can generate from an alkoxysilane compound when such a resin composition as above is thermally melted. WO 2006/051658 (claims), which was published after the priority date of this disclosure, discloses a biaxially orientated polyarylene sulfide film with an improved tensile elongation that is produced from PPS and a PEI or PES resin composition, and the addition of an alkoxysilane compound containing an isocyanate group is referred to in a paragraph for detailed description of the invention. No description is given, however, about the volume of alcohols that can generate from the alkoxysilane compound when such a resin composition is thermally melted.
Thus, no document except WO 2006/051658, which was published after the priority date of this disclosure, addresses the possibility that a resin composition with a high tensile elongation (toughness) can be produced from PPS resin containing finely dispersed PEI or PES resin with a number-average dispersed particle size of 1000 nm or less. The above-mentioned documents do not disclose the volume of alcohols that can generate from the alkoxysilane compound when such a resin composition is thermally melted.
It could therefore be helpful to provide a polyphenylene sulfide resin composition that is very high in toughness, low in gas emission during thermal melting and high in processability.